Knife sharpening device



Sept. 26, 1933. M. PRICE KNIFE SHARPENING DEVICE Filed Oct. l2,rl93l 2 Sheets-Sheet 1 Sept. 26, 1933.. M. PRICE KNIFE SHARPENING DEVICE 2 Sheets-Sheet 2 Filed Oct. 12. 1931 atented Set. i933 G DEVIGE eyer Price, Mattapan,

pplication October 12, 1931. 1am

This invention relates to knife-sharpening devices and pertains more particularly to automatic sharpeners for honing the blade of a cloth cutting machine. The principal object of the invention is to provide sharpening mechanism which may be connected to a cloth cutting machine for sliding movement longitudinally of the cutting blade, the mechanism comprising a pair of abrasive members arranged alternately to hone opposite sides of the cutting edge, a driving motor, and intermediate operative elements for reciprocating and oscillating the abrasive members with respect to the blade. Further objects reside in the construction and arrangement of the improved elements of the sharpening mechanism hereinafter described and pointed out in the appended claims.

A recommended embodiment of the invention is illustrated in the accompanying drawings, in which:

Fig. 1 is a side elevation of a cloth cutting machine equipped with the improved sharpening apparatus;

Fig. 2 is a section on line 22 of Fig. 1;

Fig. 3 is a front elevation of the apparatus;

Fig. 4 is a section to larger scale on line 4-4 of Fig. 3;

Fig. 5 is a section on line 5--5 of Fig. 4; and

Fig. 6 is a transverse section through one of the abrasive members and its holder.

The cloth cutting machine which is illustrated in conventional manner may be a portable apparatus comprising an electric motor 7 mounted upon an upright frame member 8 fixed to a base 9, and a vertically reciprocating blade 10 operated by the motor and slidable in a channel 11 of the frame 8. For the purposes of the present invention the machine is provided with a guide member 12 having grooves or channels 13 in its vertical sides; and a slide 14 having flanges 15 received within the channels 13, is removably supported upon the guide 12 and is movable vertically therein by means of a handle 16.

The slide 14 constitutes the principal supporting member of my improved knife-sharpening apparatus, and preferably has an electric motor 17 mounted upon its upper portion and a flanged plate 18 fixed at its lower end. The flanges 18 and 19 of said plate provide bearings for rotatable rods 20 and 21 having bevel gears 22 and 23 respectively fixed at their upper ends and bearing on flange 18. A transverse shaft 24 is journalerl in lugs 25 secured to said flange, and the shaft carries a pair of gears 26 and 27 meshing with the gears 22 and 23 respectively. A pulley 28 on the shaft 24 is operated by a belt 29 connected to a pulley 30 on the motor shaft 31, so that the rods 20 and 21 are rotated simultaneously on operation of the motor from a suitable power source.

The lower end portions of the rods 20 and 21 are onset to provide cranks 32 and 33 which are preferably angularly disposed with respect to each other. Hence, when the crank shafts 20 and 21 are rotated in opposite directions by the gearing above described, crank 32, for example, leads crank 33 in its orbit of revolution. These cranks are arranged to operate the knife-sharpening mechanism now to be described, and it will be apparent that one of the pair of abrasive members reaches its operative position before the other, by

reason of the aforesaid angular relation between the cranks.

A forked bracket 34, straddling the frame 8 and attached to the flange 19 of plate 18 extends rearwardly of said frame and thence down- 'wardly, terminating in a forwardly directed flange 35 having a recess 36 receiving the frame and guiding the bracket during its vertical movement. A U-shaped support 37 is fixed to the rearward surface of the vertical portion of bracket 34, and the support has a pair of similar slots 38, 38' receiving a pair of horizontal rocker arms 39, 39 which are pivoted in said support as by a bolt 40. The arms 39 and 39 are spaced one above the other and their corresponding ends are preferably provided with a series of complemental openings 41 for receiving a pair of pivot pins 44 and 45 the series of holes permitting the pins to be adjustably located along carriers 50 and 51 are pivoted at 52 and 53 to the respective sliders, and are normally urged inwardly, toward the blade 10, by yielding springs 54 and 55, the said inward movement of the carriers being limited by adjustable stop bolts 56 and 57 connecting the free ends of the carrier to the 1 respective plates.

Blocks or pieces of abrasive material 58 and 59 are mounted in suitable holders 60 and 61 of the carriers 50 and 51 respectively; and it will be apparent that the oscillating movement no imparted to the plates 42 and 43 by the crank shafts 20 and 21 will cause the plates to move in a horizontal plane and the abrasive elements alternately to engage the opposite beveled faces of the cutting blade 10; each of said elements grinding transversely of the blade toward its beveled cutting edge. This alternate operation of the abrasive elements quickly sharpens the blade at the region of application; and it is evident that the sharpening apparatus may be moved upwardly o'r downwardly as a unit upon the support 12, until the blade is sharpened along its entire working edge.

While the apparatus herein disclosed is recommended as suitable for carrying out the objects of this invention, it will be understood that its structural details may be varied to suit particular purposes without departing from the essence of this invention as defined in the following claims.

I claim:

1. In a cutting machine of the class described having an elongate blade supported for reciprocal movement, blade sharpening mechanism comprising a pair of plates mounted for oscillating and reciprocating movement in a horizontal plane at opposite sides of the blade, abrasive elements connected to the respective plates and adapted to hone opposite sides of the front cutting edge of the blade, and means for reciprocating said plates and oscillating them in opposite directions thereby alternately to swing the abrasive elements into grinding engagement with the cutting edge.

2. In a cutting machine of the class described having an elongate blade supported for reciprocal movement, blade-sharpening mechanism comprising a pair of plates mounted for oscillating and reciprocating movement at opposite sides of the blade, abrasive elements yieldingly mounted upon the respective plates and adapted to hone opposite sides of the front cutting edge of the blade, and means for reciprocating said plates and oscillating th in in opposite directions in a horizontal plane thereby alternately to swing the abrasive elements into grinding engagement with the cutting edge.

3. In a cutting machine of the class described having an elongate blade supported for reciprocal movement, blade sharpening mechanism comprising a pair of plates mounted for oscillating and reciprocating movement at opposite sides of the blade, abrasive elements connected to the respective plates and adapted to hone opposite sides of the cutting edge of the blade, and means for reciprocating said plates and oscillating them in opposite directions thereby alternately to swing the abrasive elements into grinding engagement with the cutting edge, said mechanism being slidably mounted upon the machine so that the abrasive elements and their supporting plates may be moved longitudinally of the blade.

4. In a cutting machine of the class described having an elongate blade supported for reciprocal movement, blade-sharpening mechanism comprising a pair of plates mounted for oscillating and reciprocating movement at opposite sides of the blade, abrasive elements connected to the respective plates and adapted to hone opposite sides of the cutting edge of the blade, and means for reciprocating said plates and oscillating them in opposite directions thereby alternately to swing the abrasive elements into grinding engagement with the'cutting edge, said means including a pair of rotatable shafts having crank portions angularly offset with respect to each other and pivotally connected to the respective plates.

5. In a cutting machine of the class described having an elongate blade supported for reciprocal movement, blade-sharpening mechanism comprising a pair of plates mounted for oscillating and reciprocating movement at opposite sides of the blade, abrasive elements connected to the respective plates and adapted to hone opposite sides of the cutting edge of the blade, and means for reciprocating said plates and oscillating them in opposite directions thereby alternately to swing the abrasive elements into grinding engagement with the cutting edge, said means including a pair of rotatable shafts having crank portions angularly offset with respect to each other and pivotally connected to the respective plates, and common driving mechanism for rotating said shafts in opposite directions.

6. In a cutting machine of the class described having an elongate blade supported for reciprocal movement, blade-sharpening mechanism comprising a support slidably mounted upon the ma chine, a bracket connected to said support and extending transversely of the blade, a rocker arm pivoted on said bracket, a pair of plates pivoted to the rocker arm at opposite sides of the blade, a pair of shafts having crank portions pivotally connected to the respective plates remote from the rocker pivots, said cranks being angularly MEYER PRICE. 

